Introduction to Logical Volume Management (LVM)
Managing Logical Storage Volumes
This article provides a comprehensive guide to Logical Volume Management (LVM) on Linux systems, covering key concepts, commands, and best practices for creating, resizing, and deleting volumes.
Introduction to Logical Volume Management (LVM)
Logical Volume Manager (LVM)
LVM is a powerful tool for managing logical storage volumes on Linux systems. It provides flexibility in creating, modifying, and managing disk partitions. This allows for greater control and efficiency in storage allocation.
Do You Know?
LVM improves disk space utilization by allowing you to combine physical volumes into volume groups and then create logical volumes within those groups. This provides flexibility not offered by traditional partitioning.
Concepts and Commands
Key LVM concepts include Physical Volumes (PVs), Volume Groups (VGs), and Logical Volumes (LVs). Common commands include pvcreate, vgcreate, lvcreate, vgextend, lvextend, lvreduce, vgreduce, lvremove, and vgremove.
# Example: Create a Physical Volume
pvcreate /dev/sdb
# Example: Create a Volume Group
vgcreate myvg /dev/sdb
# Example: Create a Logical Volume
lvcreate -L 10G -n mylv myvg
Important Note
Always back up your data before performing any LVM operations. Incorrect commands can lead to data loss.
Creating, Resizing, and Deleting Volumes
Creating an LVM volume involves creating PVs, VGs, and LVs. Resizing involves extending or reducing the size of LVs or VGs. Deleting involves removing LVs, VGs, or PVs.
# Example: Extend a Logical Volume
lvextend -L +5G /dev/myvg/mylv
# Example: Reduce a Logical Volume
lvreduce -L -2G /dev/myvg/mylv
# Example: Remove a Logical Volume
lvremove /dev/myvg/mylv
Avoid This
Avoid performing LVM operations while the volumes are mounted. This can lead to data corruption or system instability.
Summary
- LVM provides flexible storage management.
- Key components: PVs, VGs, LVs.
- Commands for creation, resizing, and deletion are available.
- Always back up data before performing operations.